The stent-screw assisted internal fixation (SAIF) technique: A treatment option for OF5, the three-column unstable osteoporotic vertebral fractures - A case series

Abstract

Purpose: The OF5 type of vertebral osteoporotic fracture (AO Spine-DGOU classification) represents a three-column lesion and as such is considered as highly unstable. These lesions, however, tend to affect elderly, frail patients, in whom invasive management options are limited. The stent-screw-assisted internal fixation (SAIF) technique has previously been reported as a minimally invasive treatment for osteoporotic and neoplastic vertebral fractures. Here, we sought to assess the safety and efficacy of the SAIF technique in a retrospective series of patients with thoracic OF5-fractures.

Methods: Retrospective identification, in a prospectively maintained database, of patients with OF5-fractures treated with SAIF. Intra- and post-operative complications were reported. Clinical outcome using NRS pain scale and Patient's Global Impression of Change (PGIC) and radiological outcome, with local kyphotic angle (LKA) and VB height (VBH) correction were analyzed.

Results: N = 22 consecutive patients were identified. All fractures were located in the thoracic spine. No intra-procedural complications occurred, although hospitalization-related complications did occur in 2 patients (9 %). There was a statistically significant pain reduction on follow-up. VBH restoration range was 0-12 mm (mean 5.5 mm). The mean postoperative LKA correction was 7.5°, which was maintained at last follow-up.

Conclusion: The SAIF technique appears to be a viable alternative in the management of OF5-fractures. Although it does not address all elements of OF5 instability, it appears that the stabilisation of the anterior and middle vertebral columns, coupled with the stabilising effect of the ribcage in the hypomobile thoracic spine, are biomechanically sufficient to treat OF5-fractures in this section of the spine.

Keywords: Case series; Kyphoplasty; Osteoporotic fracture; Stent-screw-assisted internal fixation (SAIF); Thoracic spine; Vertebral body.